-subject=${1//BRANCH/$branch}
-filter="sed -e 's/BRANCH/$branch/g'"
-if [ "$kconfig" ]; then
- filter="$filter -e 's/KCONFIG_NAME/$kconfig/g'"
+subject=${subject//BRANCH/$branch}
+filter=( -E -e 's/^([^ ])/|\1/' -e "s/BRANCH/$branch/g" )
+if [ -n "$kconfig" ]; then
+ filter+=( -e "s/KCONFIG_NAME/$kconfig/g" )